Treatment outcomes and esophageal cancer incidence by disease type in achalasia patients undergoing peroral endoscopic myotomy: Retrospective study.

Objectives: This retrospective study aimed to compare treatment outcomes and postoperative courses, including the incidence of esophageal cancer (EC), according to disease types, in 450 achalasia patients who underwent peroral endoscopic myotomy (POEM).

Methods: Data from consecutive POEM procedures performed from September 2011 to January 2023 at a single institution were reviewed. Achalasia was classified into straight (St), sigmoid (S1), and advanced sigmoid (S2) types using esophagography findings. Regarding efficacy, POEM was considered successful if the Eckardt score was ≤3. A statistical examination of the incidence and trend of EC occurrence across the disease type of achalasia was conducted using propensity score matching.

Results: Of the 450 patients, 349 were diagnosed with St, 80 with S1, and 21 with S2. POEM efficacy was 97.9% at 1 year and 94.2% at 2 years postprocedure, with no statistical difference between disease types. Using propensity score matching, the incidence of EC in each disease type was as follows: St, 1% (1/98); S1, 2.5% (2/77); S2, 10% (2/18). While no statistical significance was observed between St (1.0%: 1/98) and all sigmoid types (4.0%, 4/95; P = 0.3686). However, a trend test revealed a tendency for EC to occur more frequently in the order of S2, S1, and St type with a statistically significant difference (P = 0.0413).

Conclusions: Outcomes of POEM are favorable for all disease types. After POEM, it is important not only to monitor the improvement of achalasia symptoms but also to pay attention to the occurrence of EC, especially in patients with sigmoid-type achalasia.